/**
 * Project Name:fire-industry-DM-center
 * File Name:UrlFilterSecurityInterceptor.java
 * Package Name:com.firestone.config.security
 * Date:2018年3月28日下午1:29:50
 *
*/

package com.firestone.config.security;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.access.SecurityMetadataSource;
import org.springframework.security.access.intercept.AbstractSecurityInterceptor;
import org.springframework.security.access.intercept.InterceptorStatusToken;
import org.springframework.security.web.FilterInvocation;
import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;
import org.springframework.stereotype.Component;

/**
 * @Description: TODO(URL过滤安全拦截器)
 * @author CAIYJ
 * @date 2018年3月28日 下午1:29:50
 */
@Component
public class UrlFilterSecurityInterceptor extends AbstractSecurityInterceptor
        implements Filter {

    @Autowired
    private FilterInvocationSecurityMetadataSource securityMetadataSource;

    @Autowired
    public void setUrlAccessDecisionManager(
            UrlAccessDecisionManager urlAccessDecisionManager) {
        super.setAccessDecisionManager(urlAccessDecisionManager);
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

        // TODO Auto-generated method stub

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {

        FilterInvocation fi = new FilterInvocation(request, response, chain);
        invoke(fi);
    }

    @Override
    public void destroy() {

    }

    @Override
    public Class<?> getSecureObjectClass() {

        return FilterInvocation.class;
    }

    @Override
    public SecurityMetadataSource obtainSecurityMetadataSource() {

        return this.securityMetadataSource;
    }

    public void invoke(FilterInvocation fi)
            throws IOException, ServletException {
        // fi里面有一个被拦截的url
        // 里面调用UrlMetadataSource的getAttributes(Object object)这个方法获取fi对应的所有权限
        // 再调用UrlAccessDecisionManager的decide方法来校验用户的权限是否足够
        InterceptorStatusToken token = super.beforeInvocation(fi);
        try {
            // 执行下一个拦截器
            fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
        } finally {
            super.afterInvocation(token, null);
        }
    }

}
